CVE-2019-12524

Squid vulnerability

CVSS

9.8

EPSS

4.2%

EPSS pct

90th

Exploited

No known

An issue was discovered in Squid through 4.7. When handling requests from users, Squid checks its rules to see if the request should be denied. Squid by default comes with rules to block access to the Cache Manager, which serves detailed server information meant for the maintainer. This rule is implemented via url_regex. The handler for url_regex rules URL decodes an incoming request. This allows an attacker to encode their URL to bypass the url_regex check, and gain access to the blocked resource.

Affected vendor

Squid Cache

Affected product

Squid

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness type (CWE)

CWE-306 — Missing Authentication for Critical Function

Published

2020-04-15

Risk analysis

Based on its CVSS vector, this vulnerability is exploitable over the network, low attack complexity, requiring no privileges, no user interaction. Successful exploitation leads to high impact to confidentiality, high impact to integrity, high impact to availability.

Its EPSS score of 4.2% reflects a lower probability of exploitation activity in the wild over the next 30 days, placing it above 90% of all scored CVEs.

Check your external exposure to CVE-2019-12524

Confirm whether Squid Cache Squid is running on any internet-facing host or subdomain.
Match discovered service fingerprints against the version affected by CVE-2019-12524.
Prioritise remediation if the asset is public, business-critical, or near authentication/payment flows.

How ThreatPort helps with CVE-2019-12524

ThreatPort's external attack surface scanner checks your internet-facing assets — agentlessly, from the outside in — for the exposed services and versions that CVE-2019-12524 affects, then prioritises the finding by real risk using CISA KEV and FIRST.org EPSS.

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